In need of advice

Hi,

I am really sorry if this gets long winded but I am after advice from people who really know, who live with Autisum day in and day out.  I also feel a little bit of a fraud as I do not know if  my son is Autistic or not  but i have read and read and read more and  some articals i am sure I need to get him the assistance he would benifit from , then others I think thats not him at all. so now totally confused and i do not want to put him through the additional anxity of doctors and test without more advice from people like yourselves who know the real day to day life with Autisum..  I hope all of that makes sense. :/

So my son is 5 , to all intense and purposes he is like every other child , he prefers his own company but is also happy if in the right mood to play with others without any problems, he is above his expected levels at reading and maths,  his speech is as it should be infact he speaks very clearly and if anything over pronouces words, he rarly  uses can't he will say cannot  that kind of thing. all posative and good yes ?   now the things that concern me.   he is very perticular .. he likes everything in it's place , he  plays with cars, they have to be ordered by colour and size, he had curtains round his bed  1 set red and white spot, 1 set blue and white spot every night we HAD to overlay the red over the blue or we had melt down. I have since taken them down.   It is not to the extent it causes issues when out and about, although if things are routine he certainly copes better. This rarly happends in our home with so may of us.   . He has 5 other siblings and he plays with no issues great but I watch him and if things are not going right you can almost see like the cartoon caratures where they build to boiling point he clentches his fist his, face screws up and he lashes out ,   he has never done this at school but he will with his sibling, although do not get me wrong they often do deserve it! .

My main concern is his over whelming anxity  he wakes in the night with nightmares   2-3 times a week and takes hours to re settle.  when he is feeling fragile  melt down can start because I looked at him wrong..  day or night, even from giggling like a loon with his brother to melt sown within seconds, he also seems to have a low tolerance of noise, saying it makes his tummy hurt and makes him cry, the school dinner hall is the lastest thing to be upsetting him as it is too loud so he does not want to go to school  ect ect. he is the second youngest with  his younger brother 4 years old but they are like twin, same size, they wear the same clothes, shoes ect all by their own choice, but He is the total opposite a total blunder bus. no fear of anything at all.  then he has his sister who is 6 his next brother who is 9 and then two older siblings 16 and 18.  I am so sorry this has rambled on but I do not know where eles to turn, I hate to see him so upset over things  and so anxious  over simple things but this and the noise thing seem to be the only  links with autisum so i do not know if i am totally barking up the wrong tree. Any advice would be very welcomed as if there are  was i can learn to help him cope  more i will do what ever it takes. Thank you in advance